Optical transmission system and optical transmission apparatus used therefor
AssigneeMatsushita Electric Industrial Co., Ltd.
InventorsYoshikazu Ishii, Susumu Kirii, Hideto Takahashi, Kuniharu Itakura, Shinshi Kuno
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Abstract
Optical transmission being performed by frequency modulating frequency-division-multiplexed multi-channel signals as a single unit, distortion that is caused by a ripple-shaped group delay deviation in a transmitter 2, a receiver 4 and an optical link 3 is reduced by providing a level adjuster 2a for adjusting the level of frequency-division-multiplexed multi-channel signals input to the FM modulator 2b, and by increasing the input level of multi-channel signals to the FM modulator 2b by level adjusting means 2a to enlarge the bandwidth of FM signal, in the case where the number of channels is small.
Claims10
An optical transmission system comprising:
- a transmitter for transmitting optical signals based on frequency-division-multiplexed (FDM) multiplexed-channel input signals that have been multiplexed using frequency-division-multiplexing;
- and
- a receiver for receiving said optical signals transmitted from said transmitter through optical transmission means, wherein
- said transmitter having a signal level adjusting section for reducing a ripple-shaped distortion caused by a group delay deviation from at least one of said transmitter, said receiver, and said optical transmission means when-said said signal level adjusting section adjusting signal levels of transmitted signals to be constant in accordance with the number of channels of said multiplexed-channel input signals.
A transmitter used for an optical transmission system comprising:
- a transmitter for transmitting optical signals to a receiver based on multiplexed-channel input signals that have been multiplexed using frequency-division-multiplexing (FDM), wherein said transmitter has a signal level adjusting means for reducing a ripple-shaped distortion caused by a group delay deviation from in at least one of said transmitter, said receiver, and an optical transmission means between said transmitter and said receiver, said signal level adjusting section adjusting signal levels of transmitted signals to be constant in accordance with the number of channels of said multiplexed-channel input signals.
Dependencies are inferred from the claim text.